The digital camera as a GPS compass: Location matching using point clouds

We focus on the potential of a camera to act as a location sensor, assisting other location sensors to improve positioning accuracy. A camera is installed in almost all mobile devices. Moreover, the camera can be used as a location sensor without additional transmitters or receivers. However, if the camera is used as a location sensor, reliable maps will be required. Although there are some location-matching approaches that use maps, the success rate of location detection depends on the representation of a 3-D model and its information content. Compared with a model representation based on Computer-Aided Design (CAD), a point-cloud representation is more photorealistic. We therefore focus on point-cloud data being used for reliable maps. Our proposed locationmatching methodology is based on image matching using images from a digital camera and panoramic images generated from a massive point-cloud in an image-based Geographic Information System (GIS). We conducted experiments in location matching using a digital camera to supply the input data for location detection and a point cloud taken from a terrestrial laser scanner. We have confirmed that our approach can detect locations using a digital camera that is restricted to horizontal movement.